Donald Trump has bowed to overwhelming pressure and directly condemned the Ku Klux Klan, neo-Nazis and white supremacists, two days after violent clashes left one woman dead.

“Racism is evil,” the US president said at the White House. “And those who cause violence in its name are criminals and thugs, including the KKK, neo-Nazis, white supremacists, and other hate groups that are repugnant to everything we hold dear as Americans.”

The explicit remarks came after a storm of criticism – some from prominent figures in his own party – over Trump’s decision not to criticise head-on the white supremacist groups that targeted Charlottesville, Virginia, at the weekend.

He returned to Washington from his golf club in Bedminster, New Jersey, on Monday and discussed the tragedy with attorney general Jeff Sessions and new FBI director, Christopher Wray.

Reading from a teleprompter, Trump then confirmed that the justice department has opened a civil rights investigation into the car attack that killed one woman and injured 20 others. “To anyone who acted criminally in this weekend’s racist violence, you will be held fully accountable,” he insisted. “Justice will be delivered.

“As I said on Saturday, we condemn in the strongest possible terms this egregious display of hatred, bigotry, and violence. It has no place in America.”

The comments, seen as long overdue, had a mixed reception. Mark Warner, Democratic senator for Virginia, welcomed them as “presidential” but told the MSNBC channel: “I wish that he would have said those same words on Saturday when local leaders, elected leaders across the country were calling out this vileness that was exhibited on Saturday. I’m disappointed that it took him a couple of days ... but I will give the president the benefit today. He said the words.”

Rev Al Sharpton, a veteran civil rights activist, told the same news channel: “It took 48 hours. We had the head of state of Germany speak before we had the president of this country. He never really talked about these groups in their very existence stand against the values this country represents ... His silence spoke volumes to people. It was too little, too late.”

Trump still stopped short of describing Saturday’s violence as an act of terrorism, as Sessions has done. The attorney general – with whom the president has frequently clashed over the Russia inquiry in recent weeks – told the ABC channel the “evil attack” in Charlottesville “does meet the definition of domestic terrorism in our statute”.

The weekend’s violence – prompted by a white nationalist rally opposing a plan to remove from a Charlottesville park a statue of the Confederate general Robert E Lee – saw a 32-year-old woman who was protesting against hate groups, Heather Heyer, killed after being run over by a car. More than 30 people were injured in clashes between far right supporters and counter-protesters. Two state police officers also died in a helicopter crash after assisting in efforts to quell the unrest.

Car drives into crowd in Charlottesville, Virginia – video

James Fields, 20, of Maumee, Ohio, appeared in court on Monday morning by video link charged with the second-degree murder of Heyer, a legal assistant who had championed civil rights issues. He was denied bail at a hearing that lasted a matter of minutes and focused on the need for him to have an attorney.

Fields appeared before the circuit judge Robert Downer from the county jail on a small screen, dressed in a black and white striped jumpsuit, his head bowed for much of the short arraignment hearing.

“Mr Fields, you are charged with a number of felonies, including murder and malicious wounding,” Downer told the inmate, who wore the undercut hairstyle synonymous with the “alt-right” movement.

Asked if he had any ties to the community in Charlottesville, Fields, staring into the camera, replied: “No, sir.”

Fields was photographed earlier in the day before Saturday’s violence with a neo-Nazi group and has been said to hold views sympathetic to the far right. A high school teacher said Fields was fascinated with Nazism, idolized Adolf Hitler and had been singled out by school officials in the ninth grade for his “deeply held, radical” convictions on race.

Outside, a few hundred metres away, the statue of Lee was still spattered with fluorescent pink and green paint as small groups of activists came to sit in the recently renamed Emancipation Park.

Chris McMillan, a 20-year-old student from Washington DC, said the statue represented “division and the history of slavery in this country”. He added: “When I think of Robert E Lee, I think about oppression and enslavement.”

Later, a 24 year-old activist from New York, who would not give her name, got up and urinated on the statue’s base. “It needs to be peed on,” she said. “It’s a symbol of hate.”

The woman had been at the protests over the weekend and said she had been about 20 feet away from the car attack that killed Heyer. “It was intense and I’m still shaken up from it,” she said.

A few blocks away, at the site of Heyer’s death, a group of five women held a quiet vigil, praying by the roadside that was now covered in chalked messages, flowers, candles and a picture of Heyer. Other mourners gathered in silence, staring at the road where she fell.

Virginia governor Terry McAuliffe revealed on Monday that the far right activists had hidden caches of weapons around the city. “They had battering rams and we had picked up different weapons that they had stashed around the city,” McAuliffe told civil rights campaigner DeRay Mckesson on his podcast Pod Save the People.

Asked about the police response, which has been criticised as too passive, the governor said: “They were on very heightened alert because of the amount of weapons that we had been told [were coming in]. These folks came armed and our biggest concern was that shots would be fired and we would have a melee.”

He added: “If you see people yesterday walking down the street, DeRay, with semi-automatic rifles strapped on their body, I mean they had better armour than my state police and national guard had.”

The tragedy has renewed intense soul searching over race relations in America, where the first black president, Barack Obama, was succeeded by Trump, who is supported by some white supremacist groups and accused of appointing far right sympathisers to key positions of influence.

Critics contrasted the speed of that response to Trump’s flat-footed reaction to the violence on Saturday when he addressed the violence in broad strokes, saying that he condemned, “in the strongest possible terms, this egregious display of hatred, bigotry and violence on many sides. On many sides.”

The comments drew praise from a neo-Nazi website and there was a storm of criticism by leading Republicans such as senators Marco Rubio and Cory Gardner and New Jersey’s governor, Chris Christie, as well as a slew of Democrats.

The White House sought to limit the damage with a clarification and Trump’s vice-president spoke out against extreme groups while on a trip in Colombia. Mike Pence said: “We have no tolerance for hate and violence from white supremacists, neo-Nazis or the KKK. These dangerous fringe groups have no place in American public life and in the American debate, and we condemn them in the strongest possible terms,” according to a pooled report.

Like Sessions, Trump’s national security adviser, HR McMaster, said on Sunday that he considered the attack to be terrorism. The president’s daughter and White House aide, Ivanka Trump, tweeted on Sunday morning: “There should be no place in society for racism, white supremacy and neo-nazis.”

But her brother, Donald Trump Jr, took a different tack, retweeting a message from a fake account purporting to belong to the WikiLeaks founder Julian Assange, which said: “Trump condemned hours ago. Did Obama denounce BLM [Black Lives Matter] or Antifa [anti-fascist activists]? Hillary? CNN? Double standard is driving the hate. True equality will fix it.”